Archive for the ‘medicine’ Category

US states stopped their pandemic social restrictions too soon

October 8th, 2020
A masked man and woman walks outside a plastic barrier.

Enlarge / If you can't socially distance, a face mask helps. (credit: Christopher Furlong / Getty Images)

Many countries that controlled their COVID-19 cases in the spring are now seeing rises in infections, raising the prospect that they'll face a second wave of cases, as many epidemiological models had predicted. But in the United States, the number of cases has never dropped to low levels. Instead, it varied between high levels of infection and very high peaks in cases. Why is everything so different in the states?

While there are plenty of possible reasons, a series of new studies essentially blame all the obvious ones: the United States ended social distancing rules too soon, never built up sufficient testing and contact-tracing capabilities, and hasn't adopted habits like mask use that might help substitute for its failures elsewhere. The fact that some of these studies used very different methods to arrive at similar conclusions suggests that those conclusions are likely to hold up as more studies come in.

Too soon

One of the studies, performed by a US-South African team, looked at the relaxation of social distancing rules in the US. Its authors created a list of restrictions for each state and the District of Columbia and tracked the number of COVID-19 deaths in each state for eight weeks prior to the rules being terminated. The number of deaths was used as a proxy for the total number of cases, as the erratic availability of tests made the true infection rate difficult to determine.

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Posted in Biology, COVID-19, epidemiology, medicine, pandemic, public health, SARS-CoV-2, science | Comments (0)

A decadeslong struggle to find a virus wins the Nobel

October 5th, 2020
Image of a statue of a person, with a poster in the background.

Enlarge / This photograph of a bust of Alfred Nobel was taken just prior to the announcement of the winners of the 2020 Nobel Prize in Physiology or Medicine at the Karolinska Institute in Stockholm, Sweden, on October 5, 2020. (credit: JONATHAN NACKSTRAND / Getty Images)

The first known human cases of COVID-19 occurred in December 2019. About a month went by before the virus was identified and its complete genome sequence identified. This year's Nobel Prize in Physiology or Medicine honors a 25-year-long struggle to identify the virus we now know as hepatitis C.

The A B Cs

The hepatitis viruses are a bit confusing. There are now five of them known, and while they're united by their ability to attack the liver, they're very different in most other ways. The most significant of the viruses are hepatitis A, hepatitis B, and hepatitis C, and they're caused by three largely unrelated viruses—some even differ in their genetic material, using DNA versus RNA—with very different properties.

One of the first differences recognized by the medical research community was how the viruses spread. Hepatitis A infections can start due to contaminated water or food; in contrast, B and C are typically spread through contaminated blood or needles, making them a threat to the blood supply. The hepatitis A virus was the first identified, leaving researchers focused on the bloodborne B and C. B was the next identified, which is when this year's Nobel Laureates enter the picture.

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Posted in Biology, Hepatitis C, medicine, Nobel prize, science, virology | Comments (0)

Lawmakers Demand Scrutiny of Racial Bias in Health Algorithms

September 24th, 2020
Four Congress members say formulas that include race as a factor can hurt Black Americans’ access to care.

Posted in Business, Business / Artificial Intelligence, medicine | Comments (0)

Russian vaccine trial data has some odd-looking data [Updated]

September 5th, 2020
Image of a women in medical protective gear holding a box of samples.

Enlarge / MOSCOW, RUSSIA - SEPTEMBER 4, 2020: Medical staff with newly delivered boxes containing COVID-19 vaccine in a cold room at No2 Outpatient Clinic in southern Moscow. (credit: Stanislav Krasilnikov / Getty Images)

Update, September 9, 2020: On Monday, Enrico Bucci published an open letter outlining some concerns with the data in The Lancet paper that describes the vaccine safety tests. Bucci is an adjunct professor at Temple University who also runs a company that focuses on research integrity, so he has some history in this area. His open letter highlights a number of instances in the paper where the data for different samples produces identical or near-identical results.

While a few instances of this might be expected due to the similarities between the experiments and the small population of participants, the large number of such cases is highly unusual. And, as Bucci notes, the raw data underlying these graphs has not been made available, making it impossible to identify any innocuous reasons the results are so similar.

The letter simply calls the issue to the attention of the editors at The Lancet, where the study was published. As of today, 25 additional professors have signed it.

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Posted in Biology, COVID-19, medicine, SARS-CoV-2, science, vaccines, virology | Comments (0)

Evidence slowly building for long-term heart problems post-COVID-19

September 3rd, 2020
Image of small blue spheres surrounded by long green fibers.

Enlarge / A fluorescent image of cardiac muscle cells in culture. (credit: Douglas B. Cowan and James D. McCully, Harvard Medical School)

Coronaviruses spread primarily through material released when we breathe, and they cause respiratory symptoms. And SARS-CoV-2, with part of its name coming from "severe acute respiratory syndrome," didn't appear to be an exception. But as time went on, additional symptoms became clear—loss of smell, digestive-tract issues—and these weren't likely to be due to infection of the respiratory tract. And over time, what also became apparent is that the symptoms didn't necessarily fade when the virus was cleared.

As we've studied the virus more, we've learned that the protein it uses to latch on to cells is present in a lot of different tissues in the body, suggesting that a wide variety of different effects could be the direct product of infections of the cells there. This week, the effect that seems to be grabbing attention is heart problems, spurred by a Scientific American article that (among other things) considers the stories of professional and college athletes who have been infected. That was followed by a report that roughly 30 percent of college athletes who've contracted the virus end up with inflammation of the heart muscle called myocarditis.

Both reports are heavy on anecdote, but this is not a new thing; ESPN had reported on myocarditis in college athletes back in early August. And, more significantly, the scientific community has been looking into the issue for months. So far, its conclusion is that there are likely to be heart complications, even in patients who had mild COVID-19 symptoms. But the long-term implications of these problems aren't yet clear.

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Posted in Biology, cardiac, COVID-19, heart, medicine, SARS-CoV-2, science | Comments (0)

Musk says that Neuralink implants are close to ready for human testing

August 29th, 2020
Image of a hand holding a small metal disk.

Enlarge / Elon Musk shows the latest version of his company's implants. (credit: Neuralink)

On Friday, Elon Musk gave an update on what's probably his third-most prominent company: Neuralink. Neuralink had been pretty low profile (especially in comparison to Tesla and SpaceX) prior to this time last year, which is when Musk first went into detail about the company's goals and progress. And the goals were striking: a mass-market brain implant that could be installed by a robot via same-day surgery.

With this year's update, little has changed about the overall plan, but plenty of little details have been tweaked in the intervening 12 months. And progress has been made, in that Musk introduced his audience to a group of pigs who were already carrying what he suggested was version 0.9 of his implants, with human testing set to follow shortly.

Designs on the brain

One of the big differences between this year and last is the overall design of the implant and its supporting hardware. The original goal had been to keep the surgery simple in part by minimizing the size of the hole that needed to be made in the skull. This meant a small-diameter implant that wouldn't necessarily be placed near the neurons it interacted with and would require a connection to separate hardware placed behind the ear. All of this added to the level of complication and would necessarily require running some wires across the surface of the brain.

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Posted in Biology, brain-computer interface, Elon Musk, medicine, neuralink, neurobiology, science | Comments (0)

FDA’s promotion of post-COVID plasma treatment was as bad as it appeared

August 25th, 2020
Image of a man speaking from behind a podium.

Enlarge / FDA Commissioner Stephen Hahn, speaking at the press conference in which he badly mangled statistics. (credit: Pete Marovich/Getty Image)

After several days of rumors with ever-growing hype, the Trump administration announced on Sunday that the Food and Drug Administration was granting an Emergency Use Authorization (EUA) for a COVID-19 treatment. The move was controversial from the start, with reports indicating that the EUA was opposed by a number of health experts, including National Institutes of Health Director Francis Collins and National Institute of Allergy and Infectious Diseases Director Anthony Fauci. The press conference didn't settle matters, with a growing chorus of scientists saying that the data presented in support of the EUA had been misrepresented.

On Monday night, FDA Commissioner Stephen Hahn acknowledged that he had made a significant error in presenting the benefits of the treatment, and he followed that statement with an apology on Tuesday. But Hahn pushed back against indications that the approval of the treatment on the eve of the Republican National Convention was motivated by political pressure.

Wrong kind of risk

The treatment at issue involves taking the antibody-containing plasma from those who have recovered from a SARS-CoV-2 infection (convalescent plasma) and giving it to those currently suffering from COVID-19 symptoms. At Sunday's press conference, the principle justification for allowing this treatment under an EUA was a 35 percent drop in mortality for those receiving plasma in the first three days of treatment—specifically, Hahn said 35 of 100 people "would have been saved" by this treatment.

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Posted in antibodies, Biology, blood plasma, COVID-19, fda, medicine, Policy, SARS-CoV-2, science | Comments (0)

US childhood SARS-CoV-2 infections surging with the current peak

August 11th, 2020
Image of a child wearing a face mask and riding a bicycle.

Enlarge / NEW YORK CITY - AUGUST 08: A kid wears a face mask while riding a bicycle in Madison Square Park. (credit: Noam Galai / Getty Images)

The US is currently debating if and how schools can be reopened safely during the COVID-19 pandemic while dealing with a cloud of presidential misinformation. The debate is made difficult by a mix of ambiguous data about how much children contribute to the spread of the virus and some dramatic instances of the pandemic spreading within schools. Given the confusing and sometimes anecdotal evidence, it can be difficult to get a decent picture of how children are affected by SARS-CoV-2 and COVID-19.

Fortunately, the American Academy of Pediatrics and the Children’s Hospital Association have decided to provide some perspective. The two groups have been gathering state-level data on a number of stats in children and compiling it to produce a national picture. While there are definitely limitations to the data, the picture it paints is one in which the national surge in infections is being paralleled by a surge in cases in children, with nearly 100,000 new cases in the last two weeks of July.

Data and its limitations

The American Academy of Pediatrics and the Children’s Hospital Association have been analyzing childhood infections at weekly intervals, allowing them to track the pandemic's progression in the United States. Their most recent report covers up to July 30, and they have data going back to mid-April.

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Posted in COVID-19, medicine, public health, SARS-CoV-2, schools, science | Comments (0)

New study models ways of emerging from a pandemic lockdown

August 7th, 2020
Testing and contact tracing may be essential for exiting pandemic lockdowns.

Enlarge / Testing and contact tracing may be essential for exiting pandemic lockdowns. (credit: Sean Gallup / Getty Images)

As the scale and threat of the COVID-19 pandemic became clear, researchers who trace the spread of diseases were pretty unanimous: to buy us time to develop a therapy or vaccine, countries needed to implement heavy-handed restrictions to limit the opportunities for the virus to spread. Experts painted frightening pictures of huge peaks of infections that would overwhelm local hospital systems if lockdowns weren't put in place, leading to many unnecessary deaths. For countries like Italy and Spain, which were already in the throes of an uncontrolled spread, reality bore these predictions out. Peaks rose sharply in advance of restrictions but fell nearly as sharply once they were put in place.

But those same models also predicted that ending the restrictions would put countries at risk of a return of the virus a few months later, forcing governments to again decide between strict restrictions or an out-of-control pandemic in the next step of a cycle that would repeat until a vaccine or therapy became available. Those countries now have a somewhat different question: are there ways of controlling the virus without resorting to a cycle of on-and-off lockdowns? For countries like the US, which implemented restrictions briefly, erratically, and half heartedly, such that peaks haven't been separated by much of a trough, the same question will become relevant if we ever get the virus under control.

A new study by a large international team uses epidemiological models to explore ways of keeping things in check while allowing most of the population to resume a semi-normal life. It finds that there are ways of handling restriction easing, but they require a combination of an effective contact tracing system, extensive testing, and a willingness of households to quarantine together.

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Posted in Biology, contact tracing, COVID-19, epidemiology, lockdowns, medicine, pandemic, SARS-CoV-2, science | Comments (0)

Could we go on the offensive against emerging diseases?

July 29th, 2020
Image of a mouse.

Enlarge / Could we vaccinate these guys to save us from disease? (credit: CDC.gov)

Viruses like Ebola and the original SARS have highlighted the risks that emerging diseases pose to our modern, highly connected society. While the standard approach of isolating the infected and limiting the spread of the disease worked in those cases, it works slowly enough to make many people nervous. But the global spread of Zika and SARS-CoV-2 shows that these approaches have their limits, leaving us at risk.

Is there anything else we could do? A perspective by Scott Nuismer and James Bull of the University of Idaho suggests we now have the tools to go on the offensive against viruses before they transfer to humans. The proposal: treat animal hosts of threatening viruses with virus-based vaccines that can spread through wild populations. While there are a lot of details to work out here, the article lays out how we might determine if this could be a viable approach.

Threats and their hosts

There are a huge number of hosts that share virus with our species. These range from familiar threats, like the mammals that carry the rabies virus, to our agricultural species that have spanned flu pandemics, as well as newly emerging dangers, such as hantaviruses and coronaviruses, carried by mice and a variety of species, respectively. While there's no real pattern to the species that transfer viruses to humans, there have been successful efforts to identify the hosts from which viruses originated. Nuismer and Bull highlight the PREDICT program, run by the US Agency for International Development, which identified nearly 1,000 previously uncharacterized viruses before the Trump administration terminated it in March.

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Posted in Biology, emerging diseases, medicine, science, vaccines | Comments (0)